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排序方式: 共有596条查询结果,搜索用时 171 毫秒
171.
Annalisa Zaccaroni Camilla Niccoli Giulia Andreani Dino Scaravelli Maria Carmela Ferrante Antonia Lucisano Gloria Isani 《Central European Journal of Chemistry》2011,9(1):86-93
This study was conducted to determine heavy metals concentrations in tissues of 94 birds belonging to different species from
coastal areas of Naples and Salerno (Southern Italy) in order to provide baseline data concerning trace element levels in
wild birds living in or close to an area characterized by high anthropogenic impact. Additional aim of this study was to verify
if diet influenced metal accumulation, so birds were classified as birds of prey, fish eating birds and insectivorous birds. 相似文献
172.
Visible‐Light‐Mediated Photocatalytic Difunctionalization of Olefins by Radical Acylarylation and Tandem Acylation/Semipinacol Rearrangement
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Dr. Giulia Bergonzini Dr. Carlo Cassani Haldor Lorimer‐Olsson Johanna Hörberg Dr. Carl‐Johan Wallentin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(10):3292-3295
A novel method for the mild photoredox‐mediated tandem radical acylarylation and tandem acylation/semipinacol rearrangement has been developed. The synthesis of highly functionalized ketones bearing all‐carbon α‐ or β‐quaternary centers has been achieved using easily available symmetric aromatic carboxylic anhydrides as the acyl radical source. The method allows for a straightforward introduction of the keto functionality and concomitant construction of molecular complexity in a single operation. 相似文献
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Giulia Frosoni 《Mathematical Logic Quarterly》2016,62(3):204-214
Our work proposes to study the conuclear image of a substructural logic and in particular to investigate the relationship between a substructural logic and its conuclear image. We analyze some axioms familiar to substructural logics and we check if they: (a) are preserved under conuclear images, (b) never hold in a conuclear image, or (c) are compatible with conuclear images but are not necessarily preserved under conuclear images. Moreover, we prove that the conuclear image of any substructural logic has the disjunction property. We finally give a sufficient condition in order that an inequality is preserved under conuclear images and observe that if we slightly relax this condition, we meet counterexamples of inequalities that are not preserved under conuclear images. 相似文献
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A Semisynthetic Approach to New Immunoadjuvant Candidates: Site‐Selective Chemical Manipulation of Escherichia coli Monophosphoryl Lipid A
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Dr. Daniele D'Alonzo Manuela Cipolletti Giulia Tarantino Marcello Ziaco Dr. Giuseppina Pieretti Prof. Alfonso Iadonisi Prof. Giovanni Palumbo Dr. Alberto Alfano Dr. Mariateresa Giuliano Prof. Mario De Rosa Prof. Chiara Schiraldi Dr. Marcella Cammarota Prof. Michelangelo Parrilli Dr. Emiliano Bedini Prof. Maria M. Corsaro 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(31):11053-11063
A semisynthetic approach to novel lipid A derivatives from Escherichia coli (E. coli) lipid A is reported. This methodology stands as an alternative to common approaches based exclusively on either total synthesis or extraction from bacterial sources. It relies upon the purification of the lipid A fraction from fed‐batch fermentation of E. coli, followed by its structural modification through tailored, site‐selective chemical reactions. In particular, modification of the lipid pattern and functionalization of the phosphate group as well as of the sole primary hydroxyl group were accomplished, highlighting the unusual reactivity of the molecule. Preliminary investigations of the immunostimulating activity of the new semisynthetic lipid A derivatives show that some of them stand out as promising, new immunoadjuvant candidates. 相似文献
180.
Andrea Ravasio Laura Boggioni Giulia Scalcione Fabio Bertini Daniele Piovani Incoronata Tritto 《Journal of polymer science. Part A, Polymer chemistry》2012,50(18):3867-3874
Complex [Ti(κ2‐N,O‐{2,6‐F2C6H3N?C(Me)C(H) ?C(CF3) O})2Cl2] ( 1 ) was evaluated as catalyst for living copolymerization of ethylene (E) with norbornene (N) upon activation with dried methylaluminoxane (d‐MAO) at temperatures between 25 and 90 °C. Copolymerization performed at different [N]/[E] feed ratios afforded stereoirregular alternating high molar mass P(E‐co‐N) with narrow molar mass distribution. The living nature of E‐co‐N copolymerization by 1 /d‐MAO was demonstrated by kinetics at 50 °C. This catalyst system was used for the synthesis of block copolymers such as polyethylene (PE)‐block‐P(E‐co‐N) with a crystalline PE block and an amorphous P(E‐co‐N) block as well as P(E‐co‐N)1‐block‐P(E‐co‐N)2, having different norbornene contents in the segments and thus having different Tg values. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献